INVT GD300-004G-4, Operation Manual

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Goodrive300 inverters Installation guidelines
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Note: Select the fuse as the manual indicated. The fuse will protect the input power cable
from damage in short-circuit situations. It will protect the surrounding devices when the
internal of the inverter is short circuited.
4.4.2 Protecting the motor and motor cable in short-circuit situations
The inverter protects the motor and motor cable in a short-circuit situation when the motor
cable is dimensioned according to the rated current of the inverter. No additional protection
devices are needed.
 If the inverter is connected to multiple motors, a separate thermal overload
switch or a circuit breaker must be used for protecting each cable and motor.
These devices may require a separate fuse to cut off the short-circuit current.
4.4.3 Protecting the motor against thermal overload
According to regulations, the motor must be protected against thermal overload and the
current must be switched off when overload is detected. The inverter includes a motor
thermal protection function that protects the motor and closes the output to switch off the
current when necessary.
4.4.4 Implementing a bypass connection
It is necessary to set power frequency and variable frequency conversion circuits for the
assurance of continuous normal work of the inverter if faults occur in some significant
situations.
In some special situations, for example, if it is only used in soft start, the inverter can be
conversed into power frequency running after starting and some corresponding bypass
should be added.

Never connect the supply power to the inverter output terminals U, V and W.
Power line voltage applied to the output can result in permanent damage to
the inverter.
If frequent shifting is required, employ mechanically connected switches or contactors to
ensure that the motor terminals are not connected to the AC power line and inverter output
terminals simultaneously.